Distance measuring device and vehicle provided therewith

Abstract

A distance measuring device reduces an amount of calculations required to generate a parallax image. The distance measuring device that generates the parallax image to measure a distance includes image sensors each capturing an image, an edge image extractor that extracts an edge image in accordance with the image, the edge image including pixel values each containing identification information used to identify an edge caused by a brightness variation from light to dark or an edge caused by a brightness variation from dark to light, a binarized edge image generator that generates a binarized edge image in accordance with the identification information of the edge image, a parallax image generator that generates the parallax image from the binarized edge image, and a distance image calculator that calculates a distance image from the parallax image.

The invention claimed is: 
     
       1. A distance measuring device that generates a parallax image to measure a distance, the distance measuring device comprising:
 a plurality of image sensors each configured to capture an image; and 
 one or more processors configured or programmed to: 
 extract an edge image of each of the images, the edge image including pixel values each containing identification information used to identify an edge caused by a brightness variation from light to dark or an edge caused by a brightness variation from dark to light; 
 generate a binarized edge image of each of the edge images in accordance with the identification information of the edge image; 
 generate the parallax image by matching the binarized edge images; and 
 calculate a distance image from the parallax image; wherein 
 the binarized edge image is generated by substituting a pixel value that includes the identification information for identifying the edge in the edge image caused by the brightness variation from light to dark with a binary value, and substituting a pixel value that includes the identification information for identifying the edge in the edge image caused by the brightness variation from dark to light with another binary value. 
 
     
     
       2. The distance measuring device according to  claim 1 , wherein the identification information includes positive and negative numerals. 
     
     
       3. The distance measuring device according to  claim 1 , wherein the one or more processors are configured or programmed to substitute a pixel value without the identification information in the edge image with the binary value or the another binary value in a regular manner depending on a vertical position of the pixel value. 
     
     
       4. The distance measuring device according to  claim 1 , wherein the one or more processors are configured or programmed to substitute a pixel value without the identification information in the edge image with zero. 
     
     
       5. A distance measuring device that generates a parallax image to measure a distance, the distance measuring device comprising:
 a plurality of image sensors each configured to capture an image; and 
 one or more processors configured or programmed to: 
 extract an edge image of each of the images, the edge image including pixel values each containing identification information used to identify an edge caused by a brightness variation from light to dark or an edge caused by a brightness variation from dark to light; 
 generate a binarized edge image of each of the edge images in accordance with the identification information of the edge image; 
 generate the parallax image by matching the binarized edge images; 
 calculate a distance image from the parallax image; and 
 substitute a pixel value without the identification information in the edge image with one or another binary value in a regular manner depending on a vertical position of the pixel value; wherein 
 the regularity is alternating regularity. 
 
     
     
       6. A distance measuring device that generates a parallax image to measure a distance, the distance measuring device comprising:
 a plurality of image sensors each configured to capture an image; and 
 one or more processors configured or programmed to: 
 extract an edge image of each of the images, the edge image including pixel values each containing identification information used to identify an edge caused by a brightness variation from light to dark or an edge caused by a brightness variation from dark to light; 
 generate a binarized edge image of each of the edge images in accordance with the identification information of the edge image; 
 generate the parallax image by matching the binarized edge images; 
 calculate a distance image from the parallax image; and 
 substitute a pixel value without the identification information in the edge image with one or another binary value in a regular manner depending on a vertical position of the pixel value such that a pixel region without identification information in the edge image is substituted with a horizontal-striped region including the one and the another binary value. 
 
     
     
       7. A vehicle including the distance measuring device according to  claim 1 .